The 30-year-old is currently enjoying a season-long loan at the Ligue 1 outfit, but the relegated club's chairman has insisted that no deal is in place to sell the midfielder
The former Manchester City and Newcastle man made the loan move to Ligue 1 in August 2012 when Mark Hughes was in charge at Loftus Road, but current manager Harry Redknapp has suggested the midfielder could yet have a future with the Rs.
Barton has aimed jibes at QPR throughout the season - most recently taking exception at some of the squad's perceived poor attitudes - but Fernandes has not ruled out the 30-year-old returning to the club next season.
"Marseille have got to put an offer in. Joey is under contract and Joey would be a very useful player for QPR," Fernandes told the club's official website. "He helped Newcastle out [of the Championship]. Some would say we lacked his fighting spirit in the midfield. But if Joey and Marseille want [the transfer], then we will talk.
"However, he is a QPR player, and is contracted to QPR. That has to be a financial deal which would have to be worked out if he wants to go to Marseille, but as far as I am concerned he is a QPR player and in the summer will come back."